Rollable side wheel irrigating devices are widely used in irrigation applications where below-ground irrigating systems are not available or have not been installed, and also in applications where economy is an important consideration. Such devices typically utilize a horizontally-disposed axle attached at each end to a wheel or similar rollable support. Through the axle passes an irrigation conduit connected to a source of fluid. The conduit usually exits perpendicularly from the axle at its midpoint and projects outwardly therefrom. To the projection is rotatably connected, via a coupling, a gravity-biased sprinkler head conduit supporting a sprinkler head. The gravity bias is provided by means of a heavy mass rigidly suspended from the sprinkler conduit. Accordingly, as the side wheel irrigating device is rolled to various locations requiring irrigation, the heavy mass attached to the sprinkler conduit causes it to rotate and to thereby maintain the sprinkler head in a level or perpendicular relation to the ground. As a result, no separate positioning of the sprinkler head is required.
While the arrangement of the sprinkler conduit and the suspended mass rotatably connected to the portion of the irrigation conduit projecting from the axle is effective in maintaining a perpendicular relationship of sprinkler head to the ground, it also has several disadvantages. Primary among these is the fact that the various components in the irrigating device which maintain the sprinkler head perpendicular to the ground, such as the rotatable coupling, the sprinkler conduit connected between the coupling and the sprinkler head, and the mass or counterweight attached to the sprinkler conduit, must be made of heavy materials such as metal. Such materials are, therefore, more expensive than they otherwise need be if alternate materials could be used in the construction of the device. Furthermore, because metal components are utilized, are subject to corrosion and thus need periodic replacement.
Additionally, a basic disadvantage with the design described above is the necessity for utilizing a counterweight to maintain the sprinkler head in a level or perpendicular relationship with the ground. It would be desirable to eliminate this counterweight, and therefore to simplify the design.
Accordingly, it is the principal object of the present invention to simplify the design of that portion of a rollable side wheel irrigating device that maintains a sprinkler head attached to the device in a perpendicular relationship with the ground.
It is another object of the this invention to eliminate the counterweight currently used to level the sprinkler head.
It is still another object of the present invention to utilize corrosion-resistant, inexpensive, and lightweight materials in that portion of a rollable side wheel irrigating device which maintains the sprinkler head portion of the device in a perpendicular relationship with the ground.